The role of the lymphatic system in spread of malignancies wherein the malignant cells first invade the regional lymph nodes and then spread through the circulatory system to remote organs is well known. If the extent of metastasis of malignant cells to the lymph nodes can be accurately evaluated by the physician, he can determine more readily how best to treat the patient. The development of monoclonal antibodies possessing highly preferential binding properties has greatly improved accuracy in diagnosis of malignacies. Several U.S. patents teach methods of making such antibodies. For example, No. 4,486,538 to Bogoch and No. 4,448,890 to Smetana, et al., both of which are incorporated herein by reference, teach methods of making antibodies to detect cancer cells. However, they teach use of their products in in vitro assays. Cuttitta, et al., of this laboratory, in the text, Monoclonal Antibodies and Cancer edited by George White teach methods of preparing monoclonal antibodies having tumor-selective properties.
Weinstein, et al., in Science, Vol. 222, pages 423 to 426 teaches value of injection of antibodies into the lymph nodes to provide improved imaging. However, no endoscopic means of delivering the antibodies is taught or suggested therein.